| """This module tests SyntaxErrors. |
| |
| Here's an example of the sort of thing that is tested. |
| |
| >>> def f(x): |
| ... global x |
| Traceback (most recent call last): |
| SyntaxError: name 'x' is local and global (<doctest test.test_syntax[0]>, line 1) |
| |
| The tests are all raise SyntaxErrors. They were created by checking |
| each C call that raises SyntaxError. There are several modules that |
| raise these exceptions-- ast.c, compile.c, future.c, pythonrun.c, and |
| symtable.c. |
| |
| The parser itself outlaws a lot of invalid syntax. None of these |
| errors are tested here at the moment. We should add some tests; since |
| there are infinitely many programs with invalid syntax, we would need |
| to be judicious in selecting some. |
| |
| The compiler generates a synthetic module name for code executed by |
| doctest. Since all the code comes from the same module, a suffix like |
| [1] is appended to the module name, As a consequence, changing the |
| order of tests in this module means renumbering all the errors after |
| it. (Maybe we should enable the ellipsis option for these tests.) |
| |
| In ast.c, syntax errors are raised by calling ast_error(). |
| |
| Errors from set_context(): |
| |
| TODO(jhylton): "assignment to None" is inconsistent with other messages |
| |
| >>> obj.None = 1 |
| Traceback (most recent call last): |
| SyntaxError: assignment to None (<doctest test.test_syntax[1]>, line 1) |
| |
| >>> None = 1 |
| Traceback (most recent call last): |
| SyntaxError: assignment to None (<doctest test.test_syntax[2]>, line 1) |
| |
| It's a syntax error to assign to the empty tuple. Why isn't it an |
| error to assign to the empty list? It will always raise some error at |
| runtime. |
| |
| >>> () = 1 |
| Traceback (most recent call last): |
| SyntaxError: can't assign to () (<doctest test.test_syntax[3]>, line 1) |
| |
| >>> f() = 1 |
| Traceback (most recent call last): |
| SyntaxError: can't assign to function call (<doctest test.test_syntax[4]>, line 1) |
| |
| >>> del f() |
| Traceback (most recent call last): |
| SyntaxError: can't delete function call (<doctest test.test_syntax[5]>, line 1) |
| |
| >>> a + 1 = 2 |
| Traceback (most recent call last): |
| SyntaxError: can't assign to operator (<doctest test.test_syntax[6]>, line 1) |
| |
| >>> (x for x in x) = 1 |
| Traceback (most recent call last): |
| SyntaxError: can't assign to generator expression (<doctest test.test_syntax[7]>, line 1) |
| |
| >>> 1 = 1 |
| Traceback (most recent call last): |
| SyntaxError: can't assign to literal (<doctest test.test_syntax[8]>, line 1) |
| |
| >>> "abc" = 1 |
| Traceback (most recent call last): |
| SyntaxError: can't assign to literal (<doctest test.test_syntax[9]>, line 1) |
| |
| >>> `1` = 1 |
| Traceback (most recent call last): |
| SyntaxError: can't assign to repr (<doctest test.test_syntax[10]>, line 1) |
| |
| If the left-hand side of an assignment is a list or tuple, an illegal |
| expression inside that contain should still cause a syntax error. |
| This test just checks a couple of cases rather than enumerating all of |
| them. |
| |
| >>> (a, "b", c) = (1, 2, 3) |
| Traceback (most recent call last): |
| SyntaxError: can't assign to literal (<doctest test.test_syntax[11]>, line 1) |
| |
| >>> [a, b, c + 1] = [1, 2, 3] |
| Traceback (most recent call last): |
| SyntaxError: can't assign to operator (<doctest test.test_syntax[12]>, line 1) |
| |
| >>> a if 1 else b = 1 |
| Traceback (most recent call last): |
| SyntaxError: can't assign to conditional expression (<doctest test.test_syntax[13]>, line 1) |
| |
| From compiler_complex_args(): |
| |
| >>> def f(None=1): |
| ... pass |
| Traceback (most recent call last): |
| SyntaxError: assignment to None (<doctest test.test_syntax[14]>, line 1) |
| |
| |
| From ast_for_arguments(): |
| |
| >>> def f(x, y=1, z): |
| ... pass |
| Traceback (most recent call last): |
| SyntaxError: non-default argument follows default argument (<doctest test.test_syntax[15]>, line 1) |
| |
| >>> def f(x, None): |
| ... pass |
| Traceback (most recent call last): |
| SyntaxError: assignment to None (<doctest test.test_syntax[16]>, line 1) |
| |
| >>> def f(*None): |
| ... pass |
| Traceback (most recent call last): |
| SyntaxError: assignment to None (<doctest test.test_syntax[17]>, line 1) |
| |
| >>> def f(**None): |
| ... pass |
| Traceback (most recent call last): |
| SyntaxError: assignment to None (<doctest test.test_syntax[18]>, line 1) |
| |
| |
| From ast_for_funcdef(): |
| |
| >>> def None(x): |
| ... pass |
| Traceback (most recent call last): |
| SyntaxError: assignment to None (<doctest test.test_syntax[19]>, line 1) |
| |
| |
| From ast_for_call(): |
| |
| >>> def f(it, *varargs): |
| ... return list(it) |
| >>> L = range(10) |
| >>> f(x for x in L) |
| [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] |
| >>> f(x for x in L, 1) |
| Traceback (most recent call last): |
| SyntaxError: Generator expression must be parenthesized if not sole argument (<doctest test.test_syntax[23]>, line 1) |
| >>> f((x for x in L), 1) |
| [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] |
| |
| >>> f(i0, i1, i2, i3, i4, i5, i6, i7, i8, i9, i10, i11, |
| ... i12, i13, i14, i15, i16, i17, i18, i19, i20, i21, i22, |
| ... i23, i24, i25, i26, i27, i28, i29, i30, i31, i32, i33, |
| ... i34, i35, i36, i37, i38, i39, i40, i41, i42, i43, i44, |
| ... i45, i46, i47, i48, i49, i50, i51, i52, i53, i54, i55, |
| ... i56, i57, i58, i59, i60, i61, i62, i63, i64, i65, i66, |
| ... i67, i68, i69, i70, i71, i72, i73, i74, i75, i76, i77, |
| ... i78, i79, i80, i81, i82, i83, i84, i85, i86, i87, i88, |
| ... i89, i90, i91, i92, i93, i94, i95, i96, i97, i98, i99, |
| ... i100, i101, i102, i103, i104, i105, i106, i107, i108, |
| ... i109, i110, i111, i112, i113, i114, i115, i116, i117, |
| ... i118, i119, i120, i121, i122, i123, i124, i125, i126, |
| ... i127, i128, i129, i130, i131, i132, i133, i134, i135, |
| ... i136, i137, i138, i139, i140, i141, i142, i143, i144, |
| ... i145, i146, i147, i148, i149, i150, i151, i152, i153, |
| ... i154, i155, i156, i157, i158, i159, i160, i161, i162, |
| ... i163, i164, i165, i166, i167, i168, i169, i170, i171, |
| ... i172, i173, i174, i175, i176, i177, i178, i179, i180, |
| ... i181, i182, i183, i184, i185, i186, i187, i188, i189, |
| ... i190, i191, i192, i193, i194, i195, i196, i197, i198, |
| ... i199, i200, i201, i202, i203, i204, i205, i206, i207, |
| ... i208, i209, i210, i211, i212, i213, i214, i215, i216, |
| ... i217, i218, i219, i220, i221, i222, i223, i224, i225, |
| ... i226, i227, i228, i229, i230, i231, i232, i233, i234, |
| ... i235, i236, i237, i238, i239, i240, i241, i242, i243, |
| ... i244, i245, i246, i247, i248, i249, i250, i251, i252, |
| ... i253, i254, i255) |
| Traceback (most recent call last): |
| SyntaxError: more than 255 arguments (<doctest test.test_syntax[25]>, line 1) |
| |
| The actual error cases counts positional arguments, keyword arguments, |
| and generator expression arguments separately. This test combines the |
| three. |
| |
| >>> f(i0, i1, i2, i3, i4, i5, i6, i7, i8, i9, i10, i11, |
| ... i12, i13, i14, i15, i16, i17, i18, i19, i20, i21, i22, |
| ... i23, i24, i25, i26, i27, i28, i29, i30, i31, i32, i33, |
| ... i34, i35, i36, i37, i38, i39, i40, i41, i42, i43, i44, |
| ... i45, i46, i47, i48, i49, i50, i51, i52, i53, i54, i55, |
| ... i56, i57, i58, i59, i60, i61, i62, i63, i64, i65, i66, |
| ... i67, i68, i69, i70, i71, i72, i73, i74, i75, i76, i77, |
| ... i78, i79, i80, i81, i82, i83, i84, i85, i86, i87, i88, |
| ... i89, i90, i91, i92, i93, i94, i95, i96, i97, i98, i99, |
| ... i100, i101, i102, i103, i104, i105, i106, i107, i108, |
| ... i109, i110, i111, i112, i113, i114, i115, i116, i117, |
| ... i118, i119, i120, i121, i122, i123, i124, i125, i126, |
| ... i127, i128, i129, i130, i131, i132, i133, i134, i135, |
| ... i136, i137, i138, i139, i140, i141, i142, i143, i144, |
| ... i145, i146, i147, i148, i149, i150, i151, i152, i153, |
| ... i154, i155, i156, i157, i158, i159, i160, i161, i162, |
| ... i163, i164, i165, i166, i167, i168, i169, i170, i171, |
| ... i172, i173, i174, i175, i176, i177, i178, i179, i180, |
| ... i181, i182, i183, i184, i185, i186, i187, i188, i189, |
| ... i190, i191, i192, i193, i194, i195, i196, i197, i198, |
| ... i199, i200, i201, i202, i203, i204, i205, i206, i207, |
| ... i208, i209, i210, i211, i212, i213, i214, i215, i216, |
| ... i217, i218, i219, i220, i221, i222, i223, i224, i225, |
| ... i226, i227, i228, i229, i230, i231, i232, i233, i234, |
| ... i235, i236, i237, i238, i239, i240, i241, i242, i243, |
| ... (x for x in i244), i245, i246, i247, i248, i249, i250, i251, |
| ... i252=1, i253=1, i254=1, i255=1) |
| Traceback (most recent call last): |
| SyntaxError: more than 255 arguments (<doctest test.test_syntax[26]>, line 1) |
| |
| >>> f(lambda x: x[0] = 3) |
| Traceback (most recent call last): |
| SyntaxError: lambda cannot contain assignment (<doctest test.test_syntax[27]>, line 1) |
| |
| The grammar accepts any test (basically, any expression) in the |
| keyword slot of a call site. Test a few different options. |
| |
| >>> f(x()=2) |
| Traceback (most recent call last): |
| SyntaxError: keyword can't be an expression (<doctest test.test_syntax[28]>, line 1) |
| >>> f(a or b=1) |
| Traceback (most recent call last): |
| SyntaxError: keyword can't be an expression (<doctest test.test_syntax[29]>, line 1) |
| >>> f(x.y=1) |
| Traceback (most recent call last): |
| SyntaxError: keyword can't be an expression (<doctest test.test_syntax[30]>, line 1) |
| |
| |
| From ast_for_expr_stmt(): |
| |
| >>> (x for x in x) += 1 |
| Traceback (most recent call last): |
| SyntaxError: augmented assignment to generator expression not possible (<doctest test.test_syntax[31]>, line 1) |
| >>> None += 1 |
| Traceback (most recent call last): |
| SyntaxError: assignment to None (<doctest test.test_syntax[32]>, line 1) |
| >>> f() += 1 |
| Traceback (most recent call last): |
| SyntaxError: illegal expression for augmented assignment (<doctest test.test_syntax[33]>, line 1) |
| |
| |
| Test continue in finally in weird combinations. |
| |
| continue in for loop under finally shouuld be ok. |
| |
| >>> def test(): |
| ... try: |
| ... pass |
| ... finally: |
| ... for abc in range(10): |
| ... continue |
| ... print abc |
| >>> test() |
| 9 |
| |
| Start simple, a continue in a finally should not be allowed. |
| |
| >>> def test(): |
| ... for abc in range(10): |
| ... try: |
| ... pass |
| ... finally: |
| ... continue |
| Traceback (most recent call last): |
| ... |
| SyntaxError: 'continue' not supported inside 'finally' clause (<doctest test.test_syntax[36]>, line 6) |
| |
| This is essentially a continue in a finally which should not be allowed. |
| |
| >>> def test(): |
| ... for abc in range(10): |
| ... try: |
| ... pass |
| ... finally: |
| ... try: |
| ... continue |
| ... except: |
| ... pass |
| Traceback (most recent call last): |
| ... |
| SyntaxError: 'continue' not supported inside 'finally' clause (<doctest test.test_syntax[37]>, line 7) |
| |
| >>> def foo(): |
| ... try: |
| ... pass |
| ... finally: |
| ... continue |
| Traceback (most recent call last): |
| ... |
| SyntaxError: 'continue' not supported inside 'finally' clause (<doctest test.test_syntax[38]>, line 5) |
| |
| >>> def foo(): |
| ... for a in (): |
| ... try: |
| ... pass |
| ... finally: |
| ... continue |
| Traceback (most recent call last): |
| ... |
| SyntaxError: 'continue' not supported inside 'finally' clause (<doctest test.test_syntax[39]>, line 6) |
| |
| >>> def foo(): |
| ... for a in (): |
| ... try: |
| ... pass |
| ... finally: |
| ... try: |
| ... continue |
| ... finally: |
| ... pass |
| Traceback (most recent call last): |
| ... |
| SyntaxError: 'continue' not supported inside 'finally' clause (<doctest test.test_syntax[40]>, line 7) |
| |
| >>> def foo(): |
| ... for a in (): |
| ... try: pass |
| ... finally: |
| ... try: |
| ... pass |
| ... except: |
| ... continue |
| Traceback (most recent call last): |
| ... |
| SyntaxError: 'continue' not supported inside 'finally' clause (<doctest test.test_syntax[41]>, line 8) |
| |
| There is one test for a break that is not in a loop. The compiler |
| uses a single data structure to keep track of try-finally and loops, |
| so we need to be sure that a break is actually inside a loop. If it |
| isn't, there should be a syntax error. |
| |
| >>> try: |
| ... print 1 |
| ... break |
| ... print 2 |
| ... finally: |
| ... print 3 |
| Traceback (most recent call last): |
| ... |
| SyntaxError: 'break' outside loop (<doctest test.test_syntax[42]>, line 3) |
| |
| This should probably raise a better error than a SystemError (or none at all). |
| In 2.5 there was a missing exception and an assert was triggered in a debug |
| build. The number of blocks must be greater than CO_MAXBLOCKS. SF #1565514 |
| |
| >>> while 1: |
| ... while 2: |
| ... while 3: |
| ... while 4: |
| ... while 5: |
| ... while 6: |
| ... while 8: |
| ... while 9: |
| ... while 10: |
| ... while 11: |
| ... while 12: |
| ... while 13: |
| ... while 14: |
| ... while 15: |
| ... while 16: |
| ... while 17: |
| ... while 18: |
| ... while 19: |
| ... while 20: |
| ... while 21: |
| ... while 22: |
| ... break |
| Traceback (most recent call last): |
| ... |
| SystemError: too many statically nested blocks |
| |
| This tests assignment-context; there was a bug in Python 2.5 where compiling |
| a complex 'if' (one with 'elif') would fail to notice an invalid suite, |
| leading to spurious errors. |
| |
| >>> if 1: |
| ... x() = 1 |
| ... elif 1: |
| ... pass |
| Traceback (most recent call last): |
| ... |
| SyntaxError: can't assign to function call (<doctest test.test_syntax[44]>, line 2) |
| |
| >>> if 1: |
| ... pass |
| ... elif 1: |
| ... x() = 1 |
| Traceback (most recent call last): |
| ... |
| SyntaxError: can't assign to function call (<doctest test.test_syntax[45]>, line 4) |
| |
| >>> if 1: |
| ... x() = 1 |
| ... elif 1: |
| ... pass |
| ... else: |
| ... pass |
| Traceback (most recent call last): |
| ... |
| SyntaxError: can't assign to function call (<doctest test.test_syntax[46]>, line 2) |
| |
| >>> if 1: |
| ... pass |
| ... elif 1: |
| ... x() = 1 |
| ... else: |
| ... pass |
| Traceback (most recent call last): |
| ... |
| SyntaxError: can't assign to function call (<doctest test.test_syntax[47]>, line 4) |
| |
| >>> if 1: |
| ... pass |
| ... elif 1: |
| ... pass |
| ... else: |
| ... x() = 1 |
| Traceback (most recent call last): |
| ... |
| SyntaxError: can't assign to function call (<doctest test.test_syntax[48]>, line 6) |
| |
| >>> f(a=23, a=234) |
| Traceback (most recent call last): |
| ... |
| SyntaxError: keyword argument repeated (<doctest test.test_syntax[49]>, line 1) |
| |
| """ |
| |
| import re |
| import unittest |
| import warnings |
| |
| from test import test_support |
| |
| class SyntaxTestCase(unittest.TestCase): |
| |
| def _check_error(self, code, errtext, |
| filename="<testcase>", mode="exec", subclass=None): |
| """Check that compiling code raises SyntaxError with errtext. |
| |
| errtest is a regular expression that must be present in the |
| test of the exception raised. If subclass is specified it |
| is the expected subclass of SyntaxError (e.g. IndentationError). |
| """ |
| try: |
| compile(code, filename, mode) |
| except SyntaxError, err: |
| if subclass and not isinstance(err, subclass): |
| self.fail("SyntaxError is not a %s" % subclass.__name__) |
| mo = re.search(errtext, str(err)) |
| if mo is None: |
| self.fail("%s did not contain '%r'" % (err, errtext,)) |
| else: |
| self.fail("compile() did not raise SyntaxError") |
| |
| def test_paren_arg_with_default(self): |
| self._check_error("def f((x)=23): pass", |
| "parenthesized arg with default") |
| |
| def test_assign_call(self): |
| self._check_error("f() = 1", "assign") |
| |
| def test_assign_del(self): |
| self._check_error("del f()", "delete") |
| |
| def test_global_err_then_warn(self): |
| # Bug tickler: The SyntaxError raised for one global statement |
| # shouldn't be clobbered by a SyntaxWarning issued for a later one. |
| source = re.sub('(?m)^ *:', '', """\ |
| :def error(a): |
| : global a # SyntaxError |
| :def warning(): |
| : b = 1 |
| : global b # SyntaxWarning |
| :""") |
| warnings.filterwarnings(action='ignore', category=SyntaxWarning) |
| self._check_error(source, "global") |
| warnings.filters.pop(0) |
| |
| def test_break_outside_loop(self): |
| self._check_error("break", "outside loop") |
| |
| def test_delete_deref(self): |
| source = re.sub('(?m)^ *:', '', """\ |
| :def foo(x): |
| : def bar(): |
| : print x |
| : del x |
| :""") |
| self._check_error(source, "nested scope") |
| |
| def test_unexpected_indent(self): |
| self._check_error("foo()\n bar()\n", "unexpected indent", |
| subclass=IndentationError) |
| |
| def test_no_indent(self): |
| self._check_error("if 1:\nfoo()", "expected an indented block", |
| subclass=IndentationError) |
| |
| def test_bad_outdent(self): |
| self._check_error("if 1:\n foo()\n bar()", |
| "unindent does not match .* level", |
| subclass=IndentationError) |
| |
| def test_kwargs_last(self): |
| self._check_error("int(base=10, '2')", "non-keyword arg") |
| |
| def test_main(): |
| test_support.run_unittest(SyntaxTestCase) |
| from test import test_syntax |
| test_support.run_doctest(test_syntax, verbosity=True) |
| |
| if __name__ == "__main__": |
| test_main() |
